With the more reliable and much better shifting SX610 (and I think, the 410s too), you still get a bit of Delrin behind their chromed sheet metal derailleur arms.......for nostalgia's sake????...
At least they won't asplode on you on the road, plus they sell for very reasonable prices out there!
So there's really no reason to stay with the uber-plastified Prestiges......

Chombi